\begin{table}%t11
%\centering
\par
\caption{Number of dwarfs in each subsample.\label{tab11}}
\begin{tabular}{ccccc}
\hline
\hline
\multicolumn{1}{c}{[Fe/H]}
& \multicolumn{1}{c}{{\it Clean}}
& \multicolumn{1}{c}{Polluted}
& \multicolumn{1}{c}{{\it Clean}}
& \multicolumn{1}{c}{Polluted} \\
\multicolumn{1}{c}{}
& \multicolumn{1}{c}{}
& \multicolumn{1}{c}{({\it beta}+{\it ubvy})} 
& \multicolumn{1}{c}{} 
& \multicolumn{1}{c}{({\it beta}+{\it ubvy})} \\
\multicolumn{1}{c}{}
& \multicolumn{1}{c}{$>$5700}
& \multicolumn{1}{c}{$>$5700}
& \multicolumn{1}{c}{$>$6000}
& \multicolumn{1}{c}{$>$6000} \\
\hline
$\leq$--2.5   &  8 & 0+2  & 7 & 0+1  \\
--2.5 to --2.0 &  9 & 2+0  & 6 & 0+0  \\
--2.0 to --1.5 & 16 & 1+1  & 9 & 1+0  \\
\hline
\end{tabular}
\end{table}